Sterilizable packaging for medical products is needed to handle, store and transport medical devices, prosthetics, or accessories, such as gauze, needles, scalpels, clamps, sutures and so forth.
Usually, the product is placed in the package, the package sealed, and then the sealed package subjected to sterilizing conditions which sterilize the contents of the package. The seal must be strong enough and durable enough to withstand handling during transportation and storage; but it must be easily opened when the product is needed.
When sterilization is carried out by heating, the packaging or a portion of it must be air and steam-permeable so that the gas, usually air or steam, inside the package can escape as it expands from the heat. On the other hand, the packaging must be constructed in a manner to prevent entry of bacteria and pathogenic organisms after and during sterilization and until the package is subsequently opened.
When the package is a lid/container combination, the lid must be sealable to the container with good integrity of seal, but yet be easily peeled off while preferably leaving a trace to demonstrate proof of seal. Present lids for sealing medical products usually have the adhesive on the exterior portion of the lid that faces the container, usually a tray or bowl, that the lid is sealed to. Thus the adhesive is susceptible to contact with the product or device in the container. In addition, many present lids have the adhesive only at those portions that will register with a flange on the container, thus requiring a careful positioning of the lid on the container.
Also, for dry heat sterilization, a package is needed that can withstand temperatures in excess of 135.degree. C. Currently used materials, such a polyolefins as represented by Tyvek, deform and shrink under these temperature conditions.